CREATE CONVERSION

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CREATE CONVERSION

Defines a new encoding conversion.

Synopsis

CREATE [DEFAULT] CONVERSION name FOR source_encoding TO
dest_encoding FROM funcname

Description

CREATE CONVERSION defines a new conversion between
character set encodings. Conversion names may be used in the convert
function to specify a particular encoding conversion. Also, conversions
that are marked DEFAULT can be used for automatic encoding
conversion between client and server. For this purpose, two conversions,
from encoding A to B and from encoding B to A, must be defined.

To create a conversion, you must have EXECUTE privilege
on the function and CREATE privilege on the destination
schema.

Parameters

DEFAULT

Indicates that this conversion is the default for this particular
source to destination encoding. There should be only one default encoding
in a schema for the encoding pair.

name

The name of the conversion. The conversion name may be schema-qualified.
If it is not, the conversion is defined in the current schema. The conversion
name must be unique within a schema.

source_encoding

The source encoding name.

dest_encoding

The destination encoding name.

funcname

The function used to perform the conversion. The function name may
be schema-qualified. If it is not, the function will be looked up in
the path. The function must have the following signature:

Notes

Note that in this release of Greenplum Database, user-defined functions
used in a user-defined conversion must be defined as IMMUTABLE.
Any compiled code (shared library files) for custom functions must be
placed in the same location on every host in your Greenplum Database
array (master and all segments). This location must also be in the LD_LIBRARY_PATH
so that the server can locate the files.